Moistureproofing process

ABSTRACT

Cracks or joints in below ground level concrete construction are sealed by the process of bonding a strip of material over the crack to form a channel extending along the crack, pumping air into the channel under the strip to indicate the rate of leakage through the crack, and pumping a more or less viscous sealer into the channel according to the indicated rate of leakage through the crack, the sealer flowing into the crack to seal and waterproof the concrete construction.

United States Patent Watts 1 Mar. 7, 1972 [54] MOISTUREPROOFING PROCESSFOREIGN PATENTS 0R APPLICATIONS Inventor: Leonard Watts, 623 BranchBlvd, Cedar- 607,551 9/1938 Great Britain ..52/744 hum, 11516 767,0391/1957 Great Britain ..52/744 [22] Filed: Sept. 10, 1969 PrimaryExaminer-Frank L. Abbott [21] Appl 856592 Assistant Examiner-James L.Ridgill, Jr.

AttorneyPeter L. Tailer [52] 0.8. CI. ..52/744, 52/303, 52/309 [51] Int.Cl ..E02d 31/02, E04g 23/02 [57 ABSTRACT [58] Field of Search ..52/744,169, 302, 303, 287,

52/437, 101, 743, 304, 169 Cracks or joints in below ground levelconcrete construction are sealed by the process of bonding a strip ofmaterial over [56] References Cited the crack to form a channelextending along the crack, pumping air into the channel under the stripto indicate the rate of UNITED STATES PATENTS leakage through the crack,and pumping a more or less viscous 2,080,618 5/1937 Madsen sealer intothe channel according to the indicated rate of 2,718,329 1955 eym 61leakage through the crack, the sealer flowing into the crack to3,228,155 6 688 2 81 a seal and waterproof the concrete construction.3,236,015 2/ 1966 Rubenstein.... 3,332,185 7/1967 Adams '.52/303 2Claims, 8 Drawing Figures PATENTEDMAR 1 m2 SHEET 1 [IF 2 FIG. I

INVENTOR.

LEONARD WATTS BY 6@& .2? 7w ATTORNEY PATENTEDMAR H972 3.646.720

sum 2 OF 2 ooooooor/oo 0000000000 000000000 0000000000 oooooooooq00000000 00 0 0 0000 00 INVENTORI LEONARD WATTS BY (7W 3. 731M ATTORNEYMOISTUREPROOFING PROCESS BACKGROUND OF THE INVENTION During theconstruction of below ground level concrete and other masonry structuressuch as basements and the like, leaks permeable to hydrostatic pressuremay develop for many reasons. The settling of new construction may opencracks, particularly at places of stress concentration such as theintersection of floor slabs and upstanding footings and walls. In someinstances, the interruption of a pour or the interval between pours willresult in poor bonding to produce a leak. Such leaks become troublesomeafter heavy rains or tides which raise the water table above thefoundations to subject them to hydrostatic pressure. While interior sumppumps may remove such leakage, damp with resulting rot, mildew, odors,and the like render leaking basements unfit for residential orcommercial purposes.

The conventional method of waterproofing existing foundations againsthydrostatic pressure involves boring holes or excavating to pump clay,plastics, foam, or the like to block leakage paths through the wall andbetween the wall and the footing. Leaks from below passing between theedge of the floor and the wall or footing require breaking up theconcrete floor slab adjacent to the wall or footing to dig a drainageditch for coarse fill. A new border of the floor slab must then bepoured and a sump pump or other drainage provided for the ditch. Thisconventional method is very costly and is not always effective.

SUMMARY OF THE INVENTION Cracks in flat surfaces are cut out and a flatstrip is bonded over them and cracks in corners have a flat strip bondedat an angle in the corner so that the strips in each case formlongitudinal channels extending along the cracks. Fittings are in sertedin the strips and air is pumped into the channels to determine theamount of leakage through each section of crack. A sealer is preparedwith a higher viscosity and other desired properties for cracksdetermined to have higher leakage therethrough. Low-viscosity sealer isprepared for cracks which have a slight leakage therethrough. Theprepared sealers are then pumped under pressure through the fittingsinto the channels to fill and seal the cracks.

The process of this invention is far more economical and effective thanconventional sealing techniques. When epoxy and like sealers are used tocure and cast in place within masonry cracks, the process of thisinvention actually serves to strengthen the masonry so sealed.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a transverse vertical sectionthrough a fragment of a below ground masonry construction, such as acellar, waterproofed according to the process of this invention, theelements being used in the process of this invention being shown greatlyenlarged;

FIG. 2 is a transverse vertical section through a fragment of a belowground masonry construction showing the most usual water leakage paths;

FIG. 3 is a transverse vertical section through a fragment of a belowground level masonry construction shown waterproofed according toconventional processes;

FIG. 4 is a perspective view of a fragment of a corner of a masonryconstruction with channels shown formed over cracks therein according tothis invention;

FIG. 5 is a horizontal section through a fragment of a below groundlevel masonry room waterproofed according to the process of thisinvention;

FIG. 6 is a transverse vertical section through a masonry wallwaterproofed according to this invention;

FIG. 7 is a plan view of an element used in the process of thisinvention to form channels over flat surfaces; and

FIG. 8 is a perspective view of a fragment of one end of an element usedto form channels over cracks in corners according to the process of thisinvention.

DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in FIG. 2, conventionalbasement construction provides a footing 10 which supports a foundationwall 11 which is usually poured to be keyed in place by a tongue 12 andgroove 13. A floor slab 14 is poured abutting the footing l0 and wall11. If the ground water level 15 rises above the floor slab 14, the mostcommon leakage paths will be at 15 between the wall 11 and the footingl0 and at 16 at the edge of the floor slab 14.

As shown in FIG. 3, the conventional waterproofing of such basementconstruction is a costly and difficult process. Through exteriordrillings 17 or ditching (not shown), waterproof material 18 is appliedto seal the outside of footing l0 and wall 11. To seal the edge of floorslab 14, its outer edge must be taken up and a new edge 19 poured inplace. This is usually so unsatisfactory, since further settling andworking will cause new cracks, that a rubble filled drainage ditch 20must often be provided with a drainage means such as a sump pump.

As shown in FIG. I, the waterproofing process of this invention is moreeffective and much less costly. To seal a corner between a floor slab l4and a wall 11, the masonry surfaces are first cleaned in the area.Grinding may be required when the surfaces are degraded or coated withpaint or other material. The area may be further cleaned by being soakedwith muriatic acid or the like to attack fine particles. After cleaning,a strip 22 about one to 2 inches wide is laid at an angle and taped inplace with fiberglas tape or the like. The strip 22, temporarily held inplace by the tape 23, defines a channel 24 with the corner. A highpenetrating epoxy mixture is applied to the area above and below strip22 to penetrate and bond as shown at 26 and 27.

A suitable mixture of this purpose would be an epoxy cement in which twochemical compositions are mixed just prior to application, onecomposition reacting with the other to form a cured plastic after apredetermined time.

The addition of suitable known compositions will cause the epoxy systemto become thixotropic. Continuous brushing or rolling will then lowerviscosity and improve penetration into the cleaned concrete or masonry.The proportions of the epoxy system or mixture are varied depending uponthe condition of the masonry, its porosity, the ambient temperature,moisture conditions, etc. Maximum bonding power should be obtained toprovide astrong channel 24 for the purpose which will be described.

After the epoxy penetration and bonding has been assured at 26 and 27, amore viscous mixture is applied over the entire comer area includingstrip 22 and tapes 23. Fiber glass cloth is applied and impregnated withanother coat of epoxy to build up a strong layer 29 over channel 24.

Holes 28, as shown in FIG. 4, are then drilled and tapped for insertionof a fitting 30 into channel 24. As shown in FIG. 5, a fitting 30 isinserted at each end of each channel section 31. The channel sections orlengths 31 are determined or defined by blockages of lumps of fiberglass epoxy impregnated cloth which are allowed to cure therein.

One of the two fittings 30 in each channel section 31 is plugged and airis pumped into the other. By measuring the volume of air at a givenpressure during a given time interval passing through a leaking crackand escaping from a channel section 31, the effective cross-sectionalarea of a leak may be estimated. In addition, the flow of compressed airwill blow water from the leakage area to allow the leak to be bettersealed.

If a small amount of air escapes indicating a small effective leak area,a viscous sealer fluid is prepared. If a larger amount of air escapesindicating a larger effective leak area, a more viscous sealer fluid isprepared. Larger leaks also require a sealer with a shorter cure time.Temperature and other conditions should be taken into account inpreparing a sealer for a given channel section 31. One method ofmeasuring the amount of air that passes through a given leak to estimatethe effective leak area would be to prepare a small compressed airchamber 60 with a pressure indicator 61 thereon. The chamber would thenbe charged with compressed air at a given pressure. The chamber would beconnected to a fitting 30 with hose 62 and valve 63 as shown in FIG. 5and airflow through the leak would be measured by measuring the time ittook for air pressure in the chamber 60 to drop to a given lowerpressure on the pressure indicator 61.

The sealing mixture, which is preferably an epoxy casting mixture, ispumped into one fitting 30 of a given section 31. The other fitting 30in that section 3l may be removed or opened to allow air trapped inchannel 24 to escape. Pressure may be maintained on the casting orsealing mixture during its cure period to offset shrinkage. As may beseen in FIG. 1, the sealer flows where needed in areas and 16 and setsor cures to form or castin place a solid seal 33 which extends intochannel 24. It has been found that an epoxy bond or cast in a masonrycrack is stronger than the original material and thus may actuallystrengthen a moistureproof structure.

As shown in FIG. 4, cracks 40 in flat surfaces are cut out at 41. In themanner which has been described, a strip 42 is bonded with epoxy andfiberglass cloth over cutout crack 41 to form a channel 43. The strip 42and the epoxy and fiberglass cloth 44 form a wall of channel 43 which isbonded to floor slab 14. Air and a suitably prepared sealer are pumpedthrough drilled and tapped apertures 45 at each end of crack 40 to sealit in the manner which has been described.

FIG. 6 shows a crack 46 in a wall 11 cut out to form a channel.43covered by a strip 42 which is bonded to wall 11 by epoxy and fiberglass cloth 44. A sealer 50 has been pumped into channel 43 to cast inplace and sea] crack 46.

FIG. 7 shows a sheet metal strip 50 having perforations 51 in its edges.An epoxy fluid may be painted on each side of a cut out crack and astrip 50 pressed down over it. Epoxy will flow up through theperforations 51 to cure and bond the strip 50 in position to form a wallof a channel to be used in the manner described.

FIG. 8 shows a sheet metal corner strip 53 having a solid center portion54 and two angled side portions 55 and 56 containing perforations 57.When a corner is prepared and coated with an epoxy cement adjacent tothe corner, strip 53 may be pressed in place with side portion 55against a wall and side portion 56 against a floor. The epoxy will flowthrough the perforations 57 to cure and bond the strip 53 in place.

The wall forming strips may be of any desired material. Casting orsealing materials may be varied depending upon specific conditions.Polyesters may be substituted for both channel construction and sealingand casting. Butal and silicone rubbers may be used for sealing.

lclaim 1. In the process of waterproofing below ground level masonrystructures such as basements which contain cracks, the structures beingwaterproofed from the inside against hydrostatic pressure leaks from theoutside, the steps of a. bonding a strip over a crack forming alongitudinal channel larger than the crack over the length of the crackon the inside of the masonry structure, I

b. providing an inlet through the strip leading into the iongitudinalchannel,

c. pumping air under pressure through the inlet into the channel to blowthrough the crack,

d. measuring the flow of air pumped through the inlet to determine theeffective area of the crack,

e. providing a flowing sealer with a greater viscosity for cracksdetermined to have a larger effective area,

f. pumping the flowing sealer under sufficient pressure to overcome anyexterior hydrostatic pressure through the inlet into the channel to flowinto the crack under the channel, and

g. allowing the sealer to harden in the crack and in the channelthereover.

2. The process according to claim 1 wherein said sealer is an epoxymixture which cures in said channel and in said crack.

2. The process according to claim 1 wherein said sealer is an epoxymixture which cures in said channel and in said crack.